JPH1137649A - Method and apparatus for drying strip shaped body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drying apparatus which enables uniform drying of a coat applied on a strip-shaped body. SOLUTION: A steel strip 11 is carried by rollers 13 and a resist 16 is applied to a coating roller 14 from a pipe doctor nozzle 15 and transferred onto the steel strip 11. The steep strip 11 is made horizontal with the resist 16 on the upper side and the surface of the steel strip 11 is heated by heaters 2211 , 2212 ,... 225n-1 , 225n so that the resist 16 be dried. An image of the surface of the steel strip 11 is picked up in the direction of the width by a camera 25, a temperature distribution is determined by an image processing device and the temperature distribution of the steel strip 11 is measured by thermoviewer and displayed with coloring on a monitoring device. Signals of this temperature distribution are subjected to an arithmetic processing by an arithmetic processing device, and a temperature corresponding to the direction of the width of the steel strip 11 is determined for each area of the steel strip 11 and the temperature of a corresponding heater group 221, etc., is regulated by giving a PID control to temperature controllers, so that the temperature of the steel strip be a desired set temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for drying a strip for drying a material applied to the strip.

[0002]

2. Description of the Related Art Conventionally, as a drying apparatus, for example, a drying apparatus for drying a resist or a varnish applied to a strip in a manufacturing process of a cathode ray tube shadow mask is known.

When forming a shadow mask for a cathode ray tube, a resist is applied to the front and back of the iron band, which is a belt-like body, in a resist coating step, and a pattern drawn on a glass dry plate in the exposure step is formed on both sides of the iron band. The pattern baked on the iron band in the developing step is developed, and a ferric chloride solution is sprayed on the front and back of the iron band as an etching solution, and as shown in FIG. Holes 3 having a predetermined pattern are formed.

The hole 3 of the shadow mask 1 formed in FIG. 7 is generally round and has a mortar-shaped large hole diameter φA on the fluorescent screen side and a large hole diameter on the electron gun side as shown in FIG. Mortar-shaped small hole diameter smaller in diameter than φA
B, and the large hole diameter φA and the small hole diameter φB are formed in a shape communicating with each other at the opening φC.

[0005] In particular, when unevenness occurs in the dried state in the resist drying step, the sensitivity of the resist changes, and the etching causes unevenness in the shadow mask.

On the other hand, in a shadow mask for a display tube, a hole having a desired depth from the large-diameter side is first formed, an etching-resistant varnish is embedded in a portion where the hole is formed, and then dried. And finally, the varnish is peeled off to form a shadow mask having a desired hole diameter. Since the etching is performed twice in this manner, it is referred to as two-stage etching. In the step of applying and drying this varnish, if the drying of the resist is not uniform,
There is a possibility that the film thickness of the varnish changes and the etching resistance partially changes, causing unevenness.

Therefore, in drying the resist and varnish, if the drying state is poor, the quality of the shadow mask is significantly impaired.

[0008] Usually, these drying devices measure the temperature in the drying device and adjust the heater so that the temperature becomes a desired value, or use an infrared thermometer at the outlet of the drying device. The heater is adjusted by measuring the temperature at the center of the strip.

[0009]

As described above, although it is important to dry the strip uniformly, the heater is adjusted based on the internal drying temperature or the temperature of the iron strip center. It is very difficult to obtain a uniform temperature distribution in the width direction of the iron strip.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a drying method and an apparatus for uniformly drying a strip.

[0011]

According to the present invention, there is provided a belt-like member to which a coating material is applied by a plurality of heaters which are divided in a width direction of the belt-like member and relatively moved along a longitudinal direction. While heating, the temperature of the strip heated by the plurality of heaters is measured, the temperature distribution in the width direction of the strip whose temperature distribution is measured is determined, and the heater is determined based on the temperature distribution in the width direction. By adjusting the heater in accordance with the temperature distribution in the width direction of the belt-like body, the temperature distribution in the width direction becomes substantially uniform, and the overall drying becomes substantially constant.

The temperature distribution is image-processed, the heater adjustment is calculated based on the image processing, and the heater is adjusted based on the calculation. The temperature distribution is image-processed to calculate the heater adjustment. The temperature distribution in the width direction is made more uniform by the image processing, and the overall drying becomes almost constant.

Further, a plurality of heaters are provided along the moving direction of the belt-like body to form a group, and the heater is adjusted for each group. By controlling the heater for each group, the heater can be easily formed. The temperature distribution in the width direction becomes more uniform, and the overall drying becomes almost constant.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the drying apparatus of the present invention will be described below with reference to the drawings. Note that portions corresponding to the conventional example shown in FIGS. 7 and 8 are denoted by the same reference numerals and described.

First, when forming a shadow mask,
As shown in FIG. 1, the thickness is 0.10 mm to 0.22 m.
m, iron strip 11 which is a strip with a width of 500 mm to 750 mm
A resist coating step of applying a resist on the front and back of the iron strip 11 with the resist coating device 12, an exposure step of printing a pattern drawn on a glass dry plate to be a later step (not shown) on both sides of the iron strip 11, and As shown in FIGS. 7 and 8, a desired pattern is formed through a developing step of developing the pattern baked on the iron strip 11 and an etching step of spraying a ferric chloride solution as an etchant on the front and back of the iron strip 11. Is formed.

The resist coating device 12 in the resist coating step includes a roller 13 as a moving means for transporting the iron strip 11.
A plurality of rollers are provided, and the direction of the iron strip 11 is changed while applying tension by the rollers 13, and a coating roller 14 is disposed on the upstream side of the iron strip 11 so as to face the surface of the iron strip 11. The pipe 14 is provided with a pipe doctor nozzle 15 facing the roller 14, and a resist 16 as an application material is discharged from the pipe doctor nozzle 15, and the resist 16 is applied to the surface of the iron strip 11 via the coating roller 14. It is a doctor nozzle method.

A drying oven 21 is provided downstream of the coating roller 14. The drying furnace 21 includes heaters 22 ₁₁ , 22 _{12 ,.}
22 _5n are arranged to face the resist 16 on the iron band 11, a longitudinal heater group 22 ₁ a block is formed along, 22 _2, 22 _3, 22 _4, 22 _5, respectively iron band 11 Is formed.

Further, a camera 25 as a temperature measuring means for measuring the temperature and a temperature distribution measuring means for measuring the temperature distribution is disposed on the iron strip 11 downstream of the drying furnace 21. 26 is arranged opposite to the surface of the iron strip 27. Note that the camera 25 may be provided in the drying furnace 21.

Further, as shown in FIG. 1 and FIG. 2, these heaters 22 _11, 22 _12, ..., 22 to the _5n-1, 22 _5n, the heater group 22 _1, 22 _2, 22 _3, 22 _4, 22 ₅ , the heaters 22 ₁ , 22 ₂ , 22 ₃ , 22 ₄ , 22 ₅
Temperature regulators 31 ₁ , 31 ₂ , 31 ₃ , 31 ₄ , 31 as temperature control means for controlling the temperatures of ₁₁ , 22 ₁₂ ,..., _225n-1 , _225n.
5 is installed.

Meanwhile, the camera 25 is the image processing apparatus 32 is connected as an image processing unit, the image processing apparatus 32, as shown in FIG. 3, is connected to a temperature controller 31 _{1-31 5,} processor as an arithmetic means for setting, based temperature control shaped body of the temperature controller 31 _{1-31 5} to the image processing 33
And the monitor device 34 is connected.

Next, the operation of the above embodiment will be described.

First, the iron strip 11 is transported by the roller 13, a resist 16 is applied to the coating roller 14 from the pipe doctor nozzle 15, and is transferred to the coating roller 14.
The resist 16 is transferred to the iron strip 11.

Then, the iron strip 11 is made horizontal with the resist 16 facing upward, and the surface of the iron strip 11 is heated by heaters 22 ₁₁ , 22 ₁₂ ,.
_The resist 16 is dried by heating with _5n-1 and _225n .

Further, the surface of the iron strip 11 is imaged in the width direction by the camera 25, and the image signal obtained is imaged by the image processing device 32.
Strip obtained by image processing
The temperature distribution of 11 is measured by thermopure. According to this thermopure, by measuring the temperature distribution of the strip 11 using infrared rays, it is possible to display the color on the monitor device 34 according to the measured temperature as shown in FIG.

The signal of the temperature distribution is subjected to arithmetic processing by the arithmetic processing unit 33, and as shown in FIG. 5, the areas A1, A2, A3, A4, A4, and A5 of the iron strip 11 divided into five in the width direction.
A5 is obtained, and as shown in FIG.
, A2, A3, A4, A5, the temperature corresponding to the width direction of the iron strip 11 is obtained. The respective areas A1, A2, A3 are adjusted so as to reach a desired set temperature Ct by this temperature.
, A4, A5 corresponding heater groups 22 ₁ , 22 ₂ , 22 ₃ , 2
2 _4, the temperature of 22 _5, a temperature controller 31 _1, 31 _2, 31 _3, 3
1 _4, 31 ₅ and PID adjusted by (proportional - - integral-derivative) control.

As described above, the temperature distribution in the width direction of the iron strip 11 is image-processed and calculated, whereby the temperature controllers 31 ₁ , 3
In order to control the heater groups 22 ₁ , 22 ₂ , 22 ₃ , 22 ₄ , and 25 ₂₅ arranged in the width direction, the iron strip 11 is controlled by controlling 1 ₂ , 31 ₃ , 31 ₄ , and 31 _5. Can have a uniform temperature distribution in the width direction, and the yield and quality of the shadow mask 1 can be improved.

In the above embodiment, the drying of the resist 16 has been described. However, the present invention can be similarly applied to the varnish drying apparatus in the case of the two-stage etching shown in FIG. In addition, the present invention can be applied to a drying apparatus for a strip other than the shadow mask.

[0028]

According to the present invention, the temperature of a strip heated by a plurality of heaters provided in the width direction is measured, and the temperature distribution in the width direction of the strip whose temperature distribution is measured is determined. Since the heater is adjusted based on the temperature distribution in the width direction, the temperature distribution in the width direction is substantially uniform, and the entire drying can be substantially constant.

Further, since the temperature distribution is image-processed, the heater adjustment is calculated based on the image processing, and the heater is adjusted based on this calculation. Drying can be made almost constant.

Further, a plurality of heaters are provided along the moving direction of the belt-like body to form a group and the heater is adjusted for each group. Therefore, the temperature distribution in the width direction can be more easily made substantially uniform, and the whole can be easily adjusted. Drying can be made almost constant.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a drying apparatus of the present invention.

FIG. 2 is a plan view showing an arrangement of heaters in the drying furnace.

FIG. 3 is a block diagram showing a control system of the drying device.

FIG. 4 is an explanatory diagram showing a temperature distribution of the iron strip displayed on the monitor device.

FIG. 5 is an explanatory diagram showing an area obtained by dividing the drying furnace in the width direction of the iron strip;

FIG. 6 is a graph showing a temperature distribution in a width direction of the iron strip subjected to the above-described arithmetic processing.

FIG. 7 is an explanatory diagram showing a shadow mask.

FIG. 8 is an explanatory view showing holes of a shadow mask.

[Explanation of symbols]

11 Iron band as a band 13 Roller 16 as a moving means 16 Resist 22 _{1 to} 22 ₅ Heater group 22 ₁₁ , 22 ₁₂ , ..., _225n-1 , _225n heater 25 Temperature measuring means, temperature distribution Camera 31 _{1 to} 31 ₅ as measuring means ₅ Temperature controller as temperature adjusting means 32 Image processing apparatus as image processing means 33 Arithmetic processing apparatus as arithmetic means

Claims (6)

[Claims] A heating device that heats the strip, on which the coating material has been applied, while relatively moving the strip along a longitudinal direction by a plurality of heaters that are divided and arranged in the width direction of the strip; The temperature of the band heated by the heater is measured, and the temperature distribution in the width direction of the band whose temperature distribution is measured is obtained, and the heater is adjusted based on the temperature distribution in the width direction. The method of drying the band. 2. The method for drying a belt-shaped body according to claim 1, wherein the temperature distribution is image-processed, the heater adjustment is calculated based on the image processing, and the heater is adjusted based on the calculation. 3. The heater according to claim 1, wherein a plurality of heaters are provided along the moving direction of the strip to form a group, and the heater is adjusted for each group.
Or the method for drying a strip according to 2 above. 4. A plurality of heaters which are arranged in the width direction of the strip and are heated for heating the strip to which the coating material is applied, and the strip is moved along the longitudinal direction with respect to the plurality of heaters. Moving means for relatively moving; a temperature measuring means for measuring a temperature of the strip heated by the plurality of heaters; and a temperature distribution for obtaining a temperature distribution of the strip based on the temperature measured by the temperature measuring means. An apparatus for drying a belt-shaped body, comprising: a measuring unit; and a temperature adjusting unit that adjusts the heater based on the temperature distribution in the width direction measured by the temperature distribution measuring unit. 5. An image processing means for performing image processing of a temperature distribution measured by a temperature distribution measuring means, and a calculating means for calculating adjustment of a heater based on an image processed by the image processing means. The apparatus for drying a band-shaped body according to claim 4, wherein 6. The heater according to claim 4, wherein a plurality of heaters are provided along the longitudinal direction of the strip to form a group, and the temperature adjusting means adjusts the heater for each group. For drying the web.